Question: Who is the person in the head of state of Tokugawa Shogunata?
Paraphrase: Who is the person in Tokugawa Shogunata's head of state?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q205662 wdt:P35 ?obj . ?obj wdt:P31 wd:Q5 } 
Answer: Tokugawa Ieyasu, Tokugawa Hidetada